Preparation of GHZ states via Grover's quantum searching algorithm

In this paper we propose an approach to prepare GHZ states of an arbitrary multi-particle system in terms of Grover's fast quantum searching algorithm. This approach can be regarded as an extension of the Grover's algorithm to find one or more items in an unsorted database.Comment: 9 pages, Email address: [email protected]

A Comparison of Murine Smooth Muscle Cells Generated from Embryonic versus Induced Pluripotent Stem Cells

Smooth muscle cell (SMC) differentiation and dedifferentiation play a critical role in the pathogenesis of cardiovascular diseases. The lack of a good and simple in vitro SMC differentiation system has hampered the progress of SMC field for years. The generation of such an in vitro system would be invaluable for exploring molecular mechanisms of SMC differentiation and dedifferentiation. Recently, the establishment of induced pluripotent stem (iPS) cells has offered a novel therapeutic strategy to generate patient-specific stem cell lines. Here we have investigated whether iPS cells are able to differentiate into SMCs in vitro. Mouse iPS cell (O9 and TT025) monolayers were treated with 105 mol/L all-trans retinoid acid (RA). After 8 days of RA treatment, we found that >40% of the O9 iPS cells expressed the SMC-markers including SMα-actin and SM myosin heavy chain. Also, we documented that iPS-derived SMCs acquired SMC functional characteristics including contraction and calcium influx in response to stimuli. Moreover, our results indicated that there were differences in SMC-specific gene expression patterns between SMCs derived from O9 and TT025 iPS as well as normal embryonic stem cells. These differences might be due to disparity in the current iPS technology. Taken together, our data have established a simple iPS-SMC system to generate SMCs in vitro, which has tremendous potential to generate individualized SMCs for vascular tissue engineering and personalized drug screening.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/78153/1/scd.2008.0179.pd

Efficient Genome Editing of Magnetospirillum magneticum AMB-1 by CRISPR-Cas9 System for Analyzing Magnetotactic Behavior

Magnetotactic bacteria (MTB) are a diverse group of microorganisms capable of using geomagnetic fields for navigation. This magnetotactic behavior can help microorganisms move toward favorable habitats for optimal growth and reproduction. A comprehensive understanding of the magnetotactic mechanism at molecular levels requires highly efficient genomic editing tools, which remain underdeveloped in MTB. Here, we adapted an engineered CRISPR-Cas9 system for efficient inactivation of genes in a widely used MTB model strain, Magnetospirillum magneticum AMB-1. By combining a nuclease-deficient Cas9 (dCas9) and single-guide RNA (sgRNA), a CRISPR interference system was successfully developed to repress amb0994 expression. Furthermore, we constructed an in-frame deletion mutant of amb0994 by developing a CRISPR-Cas9 system. This mutant produces normal magnetosomes; however, its response to abrupt magnetic field reversals is faster than wild-type strain. This behavioral difference is probably a consequence of altered flagella function, as suggested with our dynamics simulation study by modeling M. magneticum AMB-1 cell as an ellipsoid. These data indicate that, Amb0994 is involved in the cellular response to magnetic torque changes via controlling flagella. In summary, this study, besides contributing to a better understanding of magnetotaxis mechanism, demonstrated the CRISPR-(d)Cas9 system as a useful genetic tool for efficient genome editing in MTB

Characteristic Analysis from Excessive to Deficient Syndromes in Hepatocarcinoma Underlying miRNA Array Data

Traditional Chinese medicine (TCM) treatment is regarded as a safe and effective method for many diseases. In this study, the characteristics among excessive, excessive-deficient, and deficient syndromes of Hepatocellular carcinoma (HCC) were studied using miRNA array data. We first calculated the differentially expressed miRNAs based on random module t-test and classified three TCM syndromes of HCC using SVM method. Then, the weighted miRNA-target networks were constructed for different TCM syndromes using predicted miRNA targets. Subsequently, the prioritized target genes of upexpression network of TCM syndromes were analyzed using DAVID online analysis. The results showed that there are distinctly different hierarchical cluster and network structure of TCM syndromes in HCC, but the excessive-deficient combination syndrome is extrinsically close to deficient syndrome. GO and pathway analysis revealed that the molecular mechanisms of excessive-deficient and deficient syndromes of HCC are more complex than excessive syndrome. Furthermore, although excessive-deficient and deficient syndromes have similar complex mechanisms, excessive-deficient syndrome is more involved than deficient syndrome in development of cancer process. This study suggested that miRNAs might be important mediators involved in the changing process from excessive to deficient syndromes and could be potential molecular markers for the diagnosis of TCM syndromes in HCC

Palladium-catalyzed sequential monoarylation/amidation of C(sp^3)–H bonds: stereoselective synthesis of α-amino-β-lactams and anti-α,β-diamino acid

Pd-Catalyzed sequential monoarylation/amidation of C(sp^3)–H bonds of alanine enabled by a removable 5-methoxyquinolin-8-amine (MQ) auxiliary is described. This process is highly efficient and compatible with a variety of functional groups, providing a general and practical access to various α-amino-β-lactams. The synthetic potential of this protocol is further demonstrated by the stereoselective synthesis of orthogonally protected anti-α,β-diamino acids

A Mouse Model of Huntington’s Disease Shows Altered Ultrastructure of Transverse Tubules in Skeletal Muscle Fibers

Huntington’s disease (HD) is a fatal and progressive condition with severe debilitating motor defects and muscle weakness. Although classically recognized as a neurodegenerative disorder, there is increasing evidence of cell autonomous toxicity in skeletal muscle. We recently demonstrated that skeletal muscle fibers from the R6/2 model mouse of HD have a decrease in specific membrane capacitance, suggesting a loss of transverse tubule (t-tubule) membrane in R6/2 muscle. A previous report also indicated that Cav1.1 current was reduced in R6/2 skeletal muscle, suggesting defects in excitation–contraction (EC) coupling. Thus, we hypothesized that a loss and/or disruption of the skeletal muscle t-tubule system contributes to changes in EC coupling in R6/2 skeletal muscle. We used live-cell imaging with multiphoton confocal microscopy and transmission electron microscopy to assess the t-tubule architecture in late-stage R6/2 muscle and found no significant differences in the t-tubule system density, regularity, or integrity. However, electron microscopy images revealed that the cross-sectional area of t-tubules at the triad were 25% smaller in R6/2 compared with age-matched control skeletal muscle. Computer simulation revealed that the resulting decrease in the R6/2 t-tubule luminal conductance contributed to, but did not fully explain, the reduced R6/2 membrane capacitance. Analyses of bridging integrator-1 (Bin1), which plays a primary role in t-tubule formation, revealed decreased Bin1 protein levels and aberrant splicing of Bin1 mRNA in R6/2 muscle. Additionally, the distance between the t-tubule and sarcoplasmic reticulum was wider in R6/2 compared with control muscle, which was associated with a decrease in junctophilin 1 and 2 mRNA levels. Altogether, these findings can help explain dysregulated EC coupling and motor impairment in Huntington’s disease